Virtualization of tangible interface objects

ABSTRACT

An example system includes a computing device located proximate to a physical activity surface, a video capture device, and a detector. The video capture device is coupled for communication with the computing device and is adapted to capture a video stream that includes an activity scene of the physical activity surface and one or more interface objects physically intractable with by a user. The detector processes the video stream to detect the one or more interface objects included in the activity scene, to identify the one or more interface objects that are detectable, to generate one or more events describing the one or more interface objects, and to provide the one or more events to an activity application configured to render virtual information on the one or more computing devices based on the one or more events.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. application Ser. No.15/384,075, entitled “Virtualization of Tangible Interface Objects,”filed Dec. 19, 2016, which is a continuation of U.S. application Ser.No. 15/151,213, entitled “Virtualization of Tangible Interface Objects,”filed May 10, 2016, now U.S. Pat. No. 9,552,081, which is a continuationof U.S. application Ser. No. 14/842,777, entitled “Virtualization ofTangible Interface Objects,” filed Sep. 1, 2015, now U.S. Pat. No.9,354,716, which is a continuation of U.S. application Ser. No.13/928,111, entitled “Virtualization of Tangible Interface Objects,”filed on Jun. 26, 2013, now U.S. Pat. No. 9,158,389, which claims thebenefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent ApplicationSer. No. 61/714,138, entitled “Platform Design for Adding Tangible UserInterfaces to Mobile Applications,” filed on Oct. 15, 2012, the entirecontents of each of which is incorporated herein by reference.

BACKGROUND

The present disclosure relates to virtualizing tangible interfaceobjects.

A tangible user interface is a physical environment that a user canphysically interact with to manipulate digital information. While thetangible user interface has opened up a new range of possibilities forinteracting with digital information, significant challenges remain whenimplementing such an interface. For instance, existing tangible userinterfaces generally require expensive, high-quality sensors to digitizeuser interactions with this environment, which results in systemsincorporating these tangible user interfaces being too expensive formost consumers.

SUMMARY

According to one innovative aspect of the subject matter in thisdisclosure, a physical activity surface visualization system includes acomputing device located proximate to a physical activity surface, avideo capture device, and a detector. The video capture device iscoupled for communication with the computing device and is adapted tocapture a video stream that includes an activity scene of the physicalactivity surface and one or more interface objects physicallyintractable with by a user. The detector is executable by one or moreprocessors of the computing device to process the video stream to detectthe one or more interface objects included in the activity scene, toidentify the one or more interface objects that are detectable, togenerate one or more events describing the one or more interfaceobjects, and to provide the one or more events to an activityapplication configured to render virtual information on the one or morecomputing devices based on the one or more events. The detector iscoupled to the video capture device to receive the video stream.

Generally another innovative aspect of the subject matter described inthis disclosure may be embodied in methods that include capturing, usinga video capture device, a video stream that includes an activity sceneof a physical activity surface and one or more interface objectsphysically intractable with by a user; processing, using one or morecomputing devices, the video stream to detect the one or more interfaceobjects included in the activity scene; identifying, using the one ormore computing devices, the one or more interface objects that aredetected; and presenting virtual information on the one or morecomputing devices based on the one or more interface objects that areidentified.

A further innovative aspect of the subject matter may generally includean adapter adapting a camera integrated with a computing device thatincludes a housing including a slot on a first side, the slot configuredto receive and retain an edge of a body of the computing device, thehousing configured to cover at least a portion of the field of view ofthe camera of the computing device, and a reflective element recessed atan angle into the first side of the housing to redirect the field ofview of the camera toward an activity surface located proximate thecomputing device.

Other implementations of one or more of these aspects includecorresponding systems, apparatus, and computer programs, configured toperform the actions of the methods, encoded on computer storage devices.These and other implementations may each optionally include one or moreof the following features.

For instance, the operations may further include processing the videostream further includes receiving an image of the activity scene,processing the image for one or more contours of each of the one or moreinterface objects included in the activity scene, constructing an objectdescription for each of the one or more interface objects based on theone or more contours, and inferring an object shape for each of the oneor more interface objects based on the object description associatedwith each of the one or more interface objects; that constructing theobject description for each of the one or more interface objectsincludes mapping the one or more contours associated with each of theone or more interface objects using a coordinate system, and inferringthe object shape for each of the one or more interface objects includesinferring the object shape for each of the one or more interface objectsbased on coordinates of the one or more contours associated with each ofthe one or more interface objects; determining one or more of anorientation and a position within the activity scene for each of the oneor more interface objects based on the object description of each of theone or more interface objects; that the virtual information is generatedbased on the one or more of the orientation and the position of each ofthe one or more interface objects; identifying the one or more interfaceobjects includes identifying each of the one or more interface objectsbased on the object shape of each of the one or more interface objects,respectively; that at least one interface object of the one or moreinterface objects includes an image and processing the video streamfurther includes processing the image of the activity scene for one ormore contours of the image of the at least one interface object andconstructing a description of the image of the at least one interfaceobject based on the one or more contours of the image; identifying theat least one interface object includes identifying the image of the atleast one interface object based on the description associated with theimage; that constructing the description of the image of the at leastone interface object includes mapping the one or more contoursassociated with the image using a coordinate system; that at least oneinterface object of the one or more interface objects includes an imageand processing the video stream further includes calculating one or moreof a moment for the image of the at least one interface object and acolor histogram for the image of the at least one interface object, andidentifying the at least one interface object includes identifying theimage of the at least one interface object based on one or more of themoment and the color histogram; that capturing, using the video capturedevice, the video stream includes receiving an image frame portrayingthe activity scene, comparing the image portraying the activity sceneimage to a previously received image frame portraying the activityscene, determining whether a substantial difference exists between theimage frame and the previously received image frame, proceeding toprocess the video stream to detect the one or more interface objectsincluded in the activity scene if the substantial difference isdetermined to exist, and waiting for a subsequent image frame portrayingthe activity scene if the substantial difference is determined not toexist; receiving one or more events for the one or more interfaceobjects present in the activity scene; determining the one or moreinterface objects based on the one or more events; executing one or moreroutines based on the one or more interface objects to generateobject-related information visualizing the one or more interfaceobjects; that presenting the virtual information on the computing deviceincludes presenting the object-related information to visualize the oneor more interface objects to the user; generating one or more events forthe one or more interface objects, respectively, based on an identity ofeach of the interface objects; executing one or more routines based onthe one or more events to generate information related to the one ormore interface objects for presentation; that presenting the virtualinformation on the computing device includes presenting theobject-related information; that the video stream further includes asplit view having the activity scene including the activity surface anda user scene including one or more of a face and one or more extremitiesof the user; processing the user scene for a user input; and generatingthe virtual information for presentation based on the one or moreinterface objects that are identified and the user input processed fromthe user scene.

In addition, various implementations may further optionally include oneor more of the following features: an adapter covering at least aportion of the field of view of the video capture device, the adapterconfigured to redirect at least a portion of the field of view of thevideo capture device to the physical activity surface; that videocapture device is integrated with the computing device, the computingdevice includes a housing, and the adapter is coupled to the housing ofthe computing device to cover at least the portion of the field of viewof the video capture device; that the adapter includes a housing havinga slot that is configured to receive and removably retain an edge of thehousing of the computing device; a stand placeable on the activitysurface and configured to position a display of the computing device forviewing by a user, the display including the video capture device andthe video capture device facing the user; a calibrator executable by theone or more processors to calibrate the video capture device for one ormore of a geometry of the physical activity surface visualization systemand image processing performed by the detector; a stand placeable on theactivity surface and configured to position a display of the computingdevice for viewing by a user; and an adapter covering at least a portionof the field of view of a the video capture device, the video capturedevice facing the user and the adapter configured to redirect at least aportion of the field of view of the video capture device toward thephysical activity surface.

Numerous features and advantages of the technology presented herein aredescribed throughout this disclosure. However, it should be understood,however, that the features and advantages described herein are notall-inclusive and many additional features and advantages arecontemplated and fall within the scope of the present disclosure.Moreover, it should be understood that the language used in the presentdisclosure has been principally selected for readability andinstructional purposes, and not to limit the scope of the subject matterdisclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure is illustrated by way of example, and not by way oflimitation in the figures of the accompanying drawings in which likereference numerals are used to refer to similar elements.

FIGS. 1A-1C are block diagrams illustrating example configurations forvirtualizing tangible interface objects.

FIG. 2 is a block diagram illustrating an example computer system forvirtualizing tangible interface objects.

FIG. 3 is a block diagram illustrating an example computing device.

FIG. 4 is a flowchart of an example method for virtualizing tangibleinterface objects.

FIGS. 5A and 5B are flowcharts of a further example method forvirtualizing tangible interface objects.

FIGS. 6A and 6B are flowcharts of an example method for tangibleinterface object detection and recognition.

FIG. 7 is a flowchart of a further example method for tangible interfaceobject detection.

FIGS. 8A and 8B are flowcharts of a further example method for tangibleinterface object recognition.

FIG. 9 is a flowchart of an example method for detecting changes in thestate of an activity surface.

FIG. 10 is a flowchart of an example method for processing anddisplaying virtual object-related information based on the interfaceobjects identified.

FIGS. 11A-14 are examples of virtualized scenes on a computing devicegenerated based on physical scenes created by users on a physicalactivity surface.

FIGS. 15-19 depict various views of an example adapter and stand for acomputing device.

DETAILED DESCRIPTION

The technology described herein provides a platform for virtualizing aphysical environment of tangible interface (TI) objects manipulatable bythe user. In some implementations, the platform may augment a handheldcomputing device, such as a phone or tablet, with novel hardwareaccessories to make use of a built-in video camera on the computingdevice, and utilize novel computer vision algorithms to sense userinteraction with the TI objects, although numerous other implementationsand configurations of the platform are contemplated and describedherein.

This technology yields numerous advantages including, but not limitedto, providing a low-cost alternative for developing a nearly limitlessrange of applications that blend both physical and digital mediums byreusing existing hardware (e.g., camera) and leveraging novellightweight detection and recognition algorithms, having lowimplementation costs, being compatible with existing computing devicehardware, operating in real-time to provide for a rich, real-timevirtual experience, processing numerous (e.g., >15, >25, >35, etc.) TIobjects and/or TI object interactions simultaneously withoutoverwhelming the computing device, recognizing TI objects withsubstantially perfect recall and precision (e.g., 99% and 99.5%,respectively), being capable of adapting to lighting changes and wearand tear of TI objects, providing a collaborative tangible experiencebetween users in disparate locations, being intuitive to setup and useeven for young users (e.g., 3+ years old), being natural and intuitiveto use, and requiring few or no constraints on the types of TI objectsthat can be processed. For instance, in some implementations, nospecialized markers or symbols are required to be included on the TIobjects in order for the platform to recognize the TI objects.

The TI objects used by the platform may be everyday objects used by andavailable to the user, specialized objects created for a specificpurpose, a combination of the foregoing, etc. Non-limiting examples ofTI objects include various consumer products, game pieces, clothing,toys, figurines, photographs, pre-configured cards, etc. The TI objectsmay have a substantially two-dimensional or three-dimensional shape.

FIGS. 1A-1C are block diagrams illustrating example configurations 100,150, and 180 for virtualizing the TI objects. As depicted, theconfigurations 100, 150, and 180 include, in part, an activity surface102 on which TI object(s) 114 can be placed and a computing device 104that is equipped or otherwise coupled to a video capture device 110configured to capture video of the activity surface 102 and thatincludes novel software and/or hardware capable of processing the videoto detect and recognize the TI object(s) 114 and their manipulation byone or more users and provide for the virtualization and visualizationof the TI objects and/or their manipulation (e.g., see virtualized TIobject(s) 118).

While the activity surface 102 is depicted as substantially horizontalin FIGS. 1A-1C, it should be understood that the activity surface 102can be vertical or positioned at any other angle suitable to the userfor interaction. The activity surface 102 can have any color, pattern,texture, and topography. For instance, the activity surface 102 can besubstantially flat or be disjointed/discontinuous in nature.Non-limiting examples of an activity surface 102 include a table, desk,counter, ground, a wall, a whiteboard, a chalkboard, a customizedsurface, etc.

In some implementations, the activity surface 102 may be preconfiguredfor certain activities. For instance, the activity surface 102 mayconstitute or include the board of a board game. As depicted in FIG. 1B,an example configuration may include an activity surface 102 thatincludes a pre-configured board 120. The board 120 may be integratedwith the stand 106 or may be distinct from the stand 106 but placeableadjacent to the stand 106. The board 120 can indicate to the user theboundaries of the activity surface 102 that is within the field of viewof the video capture device 110. The board 120 may include a patternthat coincides with an application operable on the computing device 104.The board 120 may be configured for specific activities or may begeneric. For instance, the board 120 may include a context (e.g.,textual and/or graphical indicators) that signifies objectives for userto complete with the UI objects. As a further example, the board 120 maybe three-dimensional in nature and include various pre-configuredobjects for the user to interact with and/or that are configured forinteraction with other TI objects. In some instances, the size of theinteractive area on the board 120 may be bounded by the field of view ofthe video capture device 110 and can be adapted by the adapter 108and/or by adjusting the position of the video capture device 110. Inadditional examples, the board 120 may be a light projection (e.g.,pattern, context, shapes, etc.) projected onto the activity surface 102.

The computing device 104 included in the example configurations 100,150, and 180 may be situated on the surface 102 or otherwise proximateto the surface 102. The computing device 104 can provide the user(s)with a virtual portal for visualizing the TI objects being manipulatedby the user. For example, the computing device 104 may be placed on atable in front of a user so the user can easily see the computing device104 while interacting with different TI objects placed on the activitysurface 102. Example computing devices 104 may include, but are notlimited to, mobile phones (e.g., feature phones, smart phones, etc.),tablets, laptops, desktops, netbooks, TVs, set-top boxes, mediastreaming devices, portable media players, navigation devices, personaldigital assistants, etc.

The computing device 104 includes or is otherwise coupled (e.g., via awireless or wired connection) to a video capture device 110 (alsoreferred to herein as a camera) for capturing a video stream of theactivity surface 102. As depicted in FIGS. 1A-1C, the video capturedevice 110 may be a front-facing camera that is equipped with an adapter108 that adapts the field of view of the camera 110 to include, at leastin part, the activity surface 102. For clarity, the portion 116 of theactivity surface 102 captured by the video capture device 110 is alsointerchangeably referred to herein as the activity surface or theactivity scene.

As depicted in FIGS. 1A-1C, the computing device 104 and/or the videocapture device 110 may be positioned and/or supported by a stand 106.For instance, the stand 106 may position the display 112 of the videocapture device 110 in a position that is optimal for viewing andinteraction by the user who is simultaneously interacting with thephysical environment (activity scene 116). The stand 106 may beconfigured to rest on the activity surface 102 and receive and sturdilyhold the computing device 104 so the computing device 104 remains stillduring use.

In some implementations, the adapter 108 adapts a video capture device110 (e.g., front-facing, rear-facing camera) of the computing device 104to capture substantially only the activity scene 116, although numerousfurther implementations are also possible and contemplated. Forinstance, the camera adapter 108 can split the field of view of thefront-facing camera into two scenes as shown in FIG. 1C. In this figure,the video capture device 110 captures an activity scene 116 thatincludes a portion of the activity surface 102 situated in front of thevideo capture device 110 and captures a user scene 126 that includes theuser (who in FIG. 1C is situated substantially in front of the computingdevice 104). These scenes can be virtually rendered as shown in regions124 and 122 of the display 112. In another example, the camera adapter108 can redirect a rear-facing camera of the computing device (notshown) toward a front-side of the computing device 104 to capture theactivity scene 116 of the activity surface 102 located in front of thecomputing device 104. In some implementations, the adapter 108 candefine one or more sides of the scene being captured (e.g., top, left,right, with bottom open).

FIGS. 15-18 depict various examples of an adapter 108 and stand 106 fora computing device 104. As shown in these figures, the adapter 108 mayinclude a slot 134 for retaining (e.g., receiving, securing, gripping,etc.) an edge of the computing device 104 so as to cover at least aportion of the camera 110. The adapter 108 may include at least oneoptical element 132 (e.g., a mirror) to direct the field of view of thecamera 110 toward the activity surface 102. The computing device 104 maybe placed in and received by a compatibly sized slot 136 formed in a topside of the stand 106. The slot 136 may extend at least partiallydownward into a main body of the stand 106 at angle so that when thecomputing device 104 is secured in the slot, it is angled back forconvenient viewing and utilization by its user or users. The stand 106may include a channel 130 formed perpendicular to and intersecting withthe slot 136. The channel 130 may be configured to receive and securethe adapter 108 when not in use. For example, the adapter 108 may have atapered shape that is compatible with and configured to be easilyplaceable in the channel 130 of the stand 106. In some instances, thechannel 130 may magnetically secure the adapter 108 in place to preventthe adapter 108 from being easily jarred out of the channel 130. Forexample, the adapter 108 and the stand 106 may include compatiblemagnets that engage when the adapter 108 is aligned in the channel 130as shown in FIG. 19. The stand 106 may be elongated along a horizontalaxis to prevent the computing device 104 from tipping over when restingon a substantially horizontal activity surface (e.g., a table). Thestand 106 may include channeling for a cable that plugs into thecomputing device 104. The cable may be configured to provide power tothe computing device 104 and/or may serve as a communication link toother computing devices, such as a laptop or other personal computer.

In some implementations, the adapter 108 may include one or more opticalelements, such as mirrors and/or lenses, to adapt the standard field ofview of the video capture device 110. For instance, the adapter 108 mayinclude one or more mirrors and lenses to redirect and/or modify thelight being reflected from activity surface 102 into the video capturedevice 110. As an example, the adapter 108 may include a mirror angledto redirect the light reflected from the activity surface 102 in frontof the computing device 104 into a front-facing camera of the computingdevice 104. As a further example, many wireless handheld devices includea front-facing camera with a fixed line of sight with respect to thedisplay 112. The adapter 108 can be detachably connected to the deviceover the camera 110 to augment the line of sight of the camera 110 so itcan capture the activity surface 102 (e.g., surface of a table).

In another example, the adapter 108 may include a series of opticalelements (e.g., mirrors) that wrap light reflected off of the activitysurface 102 located in front of the computing device 104 into arear-facing camera of the computing device 104 so it can be captured.The adapter 108 could also adapt a portion of the field of view of thevideo capture device 110 (e.g., the front-facing camera) and leave aremaining portion of the field of view unaltered so that multiple scenesmay be captured by the video capture device 110 as shown in FIG. 1C. Theadapter 108 could also include optical element(s) that are configured toprovide different effects, such as enabling the video capture device 110to capture a greater portion of the activity surface 102. For example,the adapter 108 may include a convex mirror that provides a fisheyeeffect to capture a larger portion of the activity surface 102 thanwould otherwise be capturable by a standard configuration of the videocapture device 110.

In some implementations, the video capture device is configured toinclude the stand 106 within its field of view. The stand 106 may serveas a reference point for performing geometric and/or image calibrationof the camera 110. For instance, during calibration, the calibrator 302(e.g., see FIG. 3) may calibrate the camera 110 (e.g., adjust the whitebalance, focus, exposure, etc.) of the camera 110 using the stand 106.

The video capture device 110 could, in some implementations, be anindependent unit that is distinct from the computing device 104 and maybe positionable to capture the activity surface 102 or may be adapted bythe adapter 108 to capture the activity surface 102 as discussed above.In these implementations, the video capture device 110 may becommunicatively coupled via a wired or wireless connection to thecomputing device 104 to provide it with the video stream being captured.

FIG. 2 is a block diagram illustrating an example computer system 200for virtualizing tangible interface objects. The illustrated system 200includes computing devices 104 a . . . 104 n (also referred toindividually and collectively as 104) and servers 202 a . . . 202 n(also referred to individually and collectively as 202), which arecommunicatively coupled via a network 206 for interaction with oneanother. For example, the computing devices 104 a . . . 104 n may berespectively coupled to the network 206 via signal lines 208 a . . . 208n and may be accessed by users 222 a . . . 222 n (also referred toindividually and collectively as 222). The servers 202 a . . . 202 n maybe coupled to the network 206 via signal lines 204 a . . . 204 n,respectively. The use of the nomenclature “a” and “n” in the referencenumbers indicates that any number of those elements having thatnomenclature may be included in the system 200.

The network 206 may include any number of networks and/or network types.For example, the network 206 may include, but is not limited to, one ormore local area networks (LANs), wide area networks (WANs) (e.g., theInternet), virtual private networks (VPNs), mobile (cellular) networks,wireless wide area network (WWANs), WiMAX® networks, Bluetooth®communication networks, peer-to-peer networks, other interconnected datapaths across which multiple devices may communicate, variouscombinations thereof, etc.

The computing devices 104 a . . . 104 n (also referred to individuallyand collectively as 104) are computing devices having data processingand communication capabilities. For instance, a computing device 104 mayinclude a processor (e.g., virtual, physical, etc.), a memory, a powersource, a network interface, and/or other software and/or hardwarecomponents, such as front and/or rear facing cameras, display, graphicsprocessor, wireless transceivers, keyboard, camera, sensors, firmware,operating systems, drivers, various physical connection interfaces(e.g., USB, HDMI, etc.). The computing devices 104 a . . . 104 n maycouple to and communicate with one another and the other entities of thesystem 200 via the network 206 using a wireless and/or wired connection.While two or more computing devices 104 are depicted in FIG. 2, thesystem 200 may include any number of computing devices 104. In addition,the computing devices 104 a . . . 104 n may be the same or differenttypes of computing devices.

As depicted in FIG. 2, one or more of the computing devices 104 a . . .104 n may include a camera 110, a detection engine 212, and one or moreactivity applications 214 a . . . 214 n (also referred to individuallyand collectively as 214). One or more of the computing devices 104and/or cameras 110 may also be equipped with an adapter 108 as discussedelsewhere herein. The detection engine 212 is capable of detecting andrecognizing TI objects located in the activity scene 116 (on theactivity surface 102 within field of view of camera 110). The detectionengine 212 can detect the position and orientation of the objects inphysical space, detect how the objects are being manipulated by theuser, and cooperate with the activity application(s) 214 to provideusers with a rich virtual experience incorporating those objects andtheir manipulation. In some implementations, the detection engine 212processes video captured by a camera 110 to detect and recognize the TIobject(s) and their attributes, generate events based on the TI objectsand their attributes, and provide the events generated for therecognized objects to one or more activity applications 214. Theactivity application(s) 214 are capable of processing the eventsreceived from the detection engine 212 to provide the rich environmentthat blends the tangible, physical environment being manipulated by theuser with information related to and/or complementing the TI objects.Additional structure and functionality of the computing devices 104 aredescribed in further detail below with reference to at least FIG. 3.

The servers 202 may each include one or more computing devices havingdata processing, storing, and communication capabilities. For example,the servers 202 may include one or more hardware servers, server arrays,storage devices and/or systems, etc., and/or may be centralized ordistributed/cloud-based. In some implementations, the servers 202 mayinclude one or more virtual servers, which operate in a host serverenvironment and access the physical hardware of the host serverincluding, for example, a processor, memory, storage, networkinterfaces, etc., via an abstraction layer (e.g., a virtual machinemanager).

The servers 202 may include software applications operable by one ormore computer processors of the servers 202 to provide various computingfunctionalities, services, and/or resources, and to send data to andreceive data from the computing devices 104. For example, the softwareapplications may provide functionality for internet searching; socialnetworking; web-based email; blogging; micro-blogging; photo management;video, music and multimedia hosting, distribution, and sharing; businessservices; news and media distribution; user account management; or anycombination of the foregoing services. It should be understood that theservers 202 are not limited to providing the above-noted services andmay include other network-accessible services.

In some implementations, a server 202 may include a search engine forretrieving results from a data store that match one or more searchcriteria. In some instances, the search criteria may include an imageand the search engine may compare the image to images of products storedin its data store (not shown) to identify a product that matches theimage. In a further example, the detection engine 212 and/or the storage310 (e.g., see FIG. 3) may signal the search engine to provideinformation that matches an object and/or image that it has extractedfrom a video stream.

It should be understood that the system 200 illustrated in FIG. 2 isprovided by way of example, and that a variety of different systemenvironments and configurations are contemplated and are within thescope of the present disclosure. For instance, various functionality maybe moved from a server to a client, or vice versa and someimplementations may include additional or fewer computing devices,services, and/or networks, and may implement various functionalityclient or server-side. Further, various entities of the system 200 maybe integrated into to a single computing device or system or additionalcomputing devices or systems, etc.

FIG. 3 is a block diagram of an example computing device 104. Asdepicted, the computing device 104 may include a processor 312, memory314, communication unit 316, display 112, camera 110, and an inputdevice 318, which are communicatively coupled by a communications bus308. However, it should be understood that the computing device 104 isnot limited to such and may also include other elements, including, forexample, those discussed with reference to the computing devices 104 inFIGS. 1 and 2.

The processor 312 may execute software instructions by performingvarious input/output, logical, and/or mathematical operations. Theprocessor 312 have various computing architectures to process datasignals including, for example, a complex instruction set computer(CISC) architecture, a reduced instruction set computer (RISC)architecture, and/or an architecture implementing a combination ofinstruction sets. The processor 312 may be physical and/or virtual, andmay include a single core or plurality of processing units and/or cores.

The memory 314 is a non-transitory computer-readable medium that isconfigured to store and provide access to data to the other componentsof the computing device 104. In some implementations, the memory 314 maystore instructions and/or data that may be executed by the processor312. For example, the memory 314 may store the detection engine 212, theactivity applications 214 a . . . 214 n, and the camera driver 306. Thememory 314 is also capable of storing other instructions and data,including, for example, an operating system, hardware drivers, othersoftware applications, data, etc. The memory 314 may be coupled to thebus 308 for communication with the processor 312 and the othercomponents of the computing device 104.

The communication unit 316 may include one or more interface devices(I/F) for wired and/or wireless connectivity with the network 206 and/orother devices. In some implementations, the communication unit 316 mayinclude transceivers for sending and receiving wireless signals. Forinstance, the communication unit 316 may include radio transceivers forcommunication with the network 206 and for communication with nearbydevices using close-proximity (e.g., Bluetooth®, NFC, etc.)connectivity. In some implementations, the communication unit 316 mayinclude ports for wired connectivity with other devices. For example,the communication unit 316 may include a CAT-5 interface, Thunderbolt™interface, FireWire™ interface, USB interface, etc.

The display 112 may display electronic images and data output by thecomputing device 104 for presentation to a user 222. The display 112 mayinclude any conventional display device, monitor or screen, including,for example, an organic light-emitting diode (OLED) display, a liquidcrystal display (LCD), etc. In some implementations, the display 112 maybe a touch-screen display capable of receiving input from one or morefingers of a user 222. For example, the display 112 may be a capacitivetouch-screen display capable of detecting and interpreting multiplepoints of contact with the display surface. In some implementations, thecomputing device 104 may include a graphics adapter (not shown) forrendering and outputting the images and data for presentation on display112. The graphics adapter (not shown) may be a separate processingdevice including a separate processor and memory (not shown) or may beintegrated with the processor 312 and memory 314.

The input device 318 may include any device for inputting informationinto the computing device 104. In some implementations, the input device318 may include one or more peripheral devices. For example, the inputdevice 318 may include a keyboard (e.g., a QWERTY keyboard), a pointingdevice (e.g., a mouse or touchpad), microphone, a camera, etc. In someimplementations, the input device 318 may include a touch-screen displaycapable of receiving input from the one or more fingers of the user 222.For instance, the functionality of the input device 318 and the display112 may be integrated, and a user 222 of the computing device 104 mayinteract with the computing device 104 by contacting a surface of thedisplay 112 using one or more fingers. In this example, the user 222could interact with an emulated (i.e., virtual or soft) keyboarddisplayed on the touch-screen display 112 by using fingers to contactingthe display 112 in the keyboard regions.

The detection engine 212 may include a calibrator 302 and a detector304. The components 212, 302, and 304 may be communicatively coupled bythe bus 308 and/or the processor 312 to one another and/or the othercomponents 214, 306, 310, 314, 316, 318, 112, and/or 110 of thecomputing device 104. In some implementations, one or more of thecomponents 212, 302, and 304 are sets of instructions executable by theprocessor 312 to provide their functionality. In some implementations,one or more of the components 212, 302, and 304 are stored in the memory314 of the computing device 104 and are accessible and executable by theprocessor 312 to provide their functionality. In any of the foregoingimplementations, these components 212, 302, and 304 may be adapted forcooperation and communication with the processor 312 and othercomponents of the computing device 104.

The calibrator 302 includes software and/or logic for performinggeometric and image calibration of the camera 110. Geometric calibrationincludes calibrating the camera 110 to account for the geometry of theplatform/video capturing setup (e.g., see FIGS. 1A-1C). For instance,geometric calibration configures the camera 110 to account for theheight of the stand 106, angle the camera 110 and/or computing device104 are positioned at, and/or the characteristics (e.g., size, angle,topography, etc.) of the activity surface 102 and/or board 120, anyoptical effects induced by the adapter 108 and/or optics of the camera110, etc. Performing geometric calibration optimizes the images beingcaptured by the camera 110 for objection detection by the detector 304,as discussed in further detail below. Geometric calibration isadvantageous is it calibrates camera 110 to account for discontinuitiesand/or non-uniformities in activity surface 102, thus allowing thetechnology described herein to be used in a variety of differentsettings and with a wide variety of activity surface configurations(e.g., bumpy surfaces, whiteboards, tables, beds, etc.). In someimplementations, the calibrator 302 can calibrate the camera 110 tooptimize it to capture a split field of view that contains both the userin one portion and the activity surface 102 in another portion.

Image calibration includes manipulating the camera 110 to optimize imagerecognition by the detector 304. In some implementations, the calibrator302 performs image calibration by verifying and/or adjusting one or moreparameters, such as focus, exposure, white balance, aperture, f-stop,image compression, ISO, depth of field, noise reduction, focal length,etc., of the camera 110 to optimize the images of the TI objects beingcaptured by the camera 110 for image recognition, as discussed infurther detail below. For example, a known, pre-identified TI object maybe place in the activity scene, and the calibrator 302 may processimages received from the camera 110 to establish boundaries of the TIobject and change various parameters, such as the focus of the camera110, based on boundaries to optimize the images being received.

The detector 304 includes software and/or logic for processing the videostream captured by the camera 110 to detect and identify TI object(s)included in the activity scene 116. In some implementations, thedetector 304 may be couple to and receive the video stream from thecamera 110, the camera driver 306, and/or the memory 314. In someimplementations, the detector 304 may process the images of the videostream to determine positional information for the TI objects in theactivity scene 116 (e.g., location and/or orientation of the TI objectsin 2D or 3D space) and then analyze characteristics of the TI objectsincluded in the video stream to determine the identities and/oradditional attributes of the TI objects, as discussed in further detailbelow with reference to at least FIGS. 4-10.

In some implementations, the detector 304 may determine gesturesassociated with the TI objects that indicate how the TI objects havebeen manipulated over time by the user(s). For example and notlimitation, the detector 304 may determine the following gestures forthe TI objects:

-   -   Put: indicates TI object has appeared in activity scene 116;    -   Obscure: indicates TI object still present in activity scene 116        but has been partially or completely obscured (e.g., by a user's        hand);    -   Remove: indicates TI object has disappeared from the activity        scene 116;    -   Swap: indicates one TI object has been swapped in for another TI        object (in approximately the same location);    -   Rotate: indicates TI object has been rotated (e.g., clockwise by        45, 90, 135, 180, 225, 270, 315 degrees, by any floating point        value representing an angle, etc.);    -   Move: indicates object has been moved from one location to        another in the activity scene 116;    -   Align: indicates two objects are somehow aligned (e.g.,        horizontally, vertically, diagonally, etc.); and    -   Pattern: indicates TI object centers form a pattern (e.g., a        line, triangle, circle, square, rectangle, star, etc.).

The detector 304 may expose the TI objects and their attributes to theactivity applications 214. For instance, the detector 304 may generateevents for the TI objects based on the object-related informationdetermined by the detector 304 for the TI objects, and may pass theevents to the to one or more activity applications 214 for use therebyin generating rich virtual environments incorporating the TI objects. Anevent for a given TI object detected and identified by the detector 304may include one or more of the following: object ID, object confidence,size of object, shape of object, location of object (e.g., X, Y, Z),orientation of the object, whether object is obscured, how much ofobject is obscured, confidence object is obscured, gesture associatedwith object, etc.), although fewer or additional TI object attributesmay also be used. The detector 304 may be coupled to the applications214 (e.g., via the processor 312 and/or the bus 308) to provide theevents to the applications 214.

In implementations where the video stream includes multiple scenes, suchas scenes 116 and 126 in FIG. 1C, the detector 304 may process each ofthese scenes independently and simultaneously and discussed in furtherdetail below with reference to at least FIGS. 5A and 5B.

The detector 304 may be coupled to the calibrator 302 to signal it toperform geometric and/or image calibration. In some implementations, thedetector 304 may determine whether to signal the calibrator 302 tocalibrate the camera 110 based at least in part on whether objectsand/or images are being successfully detected, as discussed in furtherdetail below with reference to at least FIGS. 6A and 6B.

The detector 304 may be coupled to the storage 310 via the bus 308store, retrieve, and otherwise manipulate data stored therein. Forexample, the detector 304 may query the storage 310 for data matchingany TI objects that it has determined as present in the activity scene116. In some implementations, the detector 304 may compute uniqueindexes for the objects it detects. The detector 304 may compute theindexes based on the visible and/or audible characteristics of the TIobjects, such as images included on the TI objects, shapes of the TIobjects, colors of the TI objects, textures of the TI objects, etc. Insome implementations, each of the TI objects may include unique imagesand the detector 304 may perform image recognition on images todetermine their identities. In these implementations, correspondingdigital records for the TI objects may be indexed and stored in thestorage 310, and the detector 304 may query the storage 310 for recordsmatching the TI objects determined by the detector 304 as present in theactivity scene 116.

By way of example and not limitation, the TI objects may be a set ofequally-sized cards that each bear an image of a different animal. Arecord for each of the cards may be created and stored in the storage310. In some cases, the records corresponding to the cards may beimported into the storage 310 (e.g., by downloading them via the network206 from a remote location (e.g., a server 202). In other cases, a usermay create and store the records independently (e.g., via an applicationthat utilizes the TI object detection and index generation capability ofthe detector 304). Additional examples of TI objects are discussed belowwith reference to at least FIGS. 11A-14.

The activity applications 214 a . . . 214 n include software and/orlogic for receiving object-related events and running routines basedthereon to generate a virtual environment for presentation to the userthat incorporates, in real-time, the TI objects and their manipulation,and their relation to one another and the activity surface 102, in thephysical activity scene 116. The activity applications 214 a . . . 214 nmay be coupled to the detector 304 via the processor 312 and/or the bus308 to receive the events. In some implementations, the activityapplications 214 a . . . 214 may process the events received from thedetector 304 to determine the attributes of the object and may rendercorresponding information for display based on the attributes. Forexample, an activity application 214 may use the object ID to retrieve adigital representation of the TI object from the storage 310, may userthe object confidence to determine whether to even display informationabout the object (e.g., by comparing the object confidence to apredetermined threshold), may perform an action with the digitalrepresentation of the TI object based on the object's position and/orwhether the object (or a nearby TI object) has been manipulated, e.g.,moved, obscured, swapped, removed, newly added, etc.), may perform anaction dependent on what other objects are aligned with and/or adjacentto a given object, etc.

The activity application 214 may enhance the virtualinformation/environment it generates using supplemental informationdetermined based on the TI objects present in the activity scene 116.For example, an activity application 214 may develop a digitalrepresentation of a TI object with additional information (e.g., facts,statistics, news, video, photos, social network posts, microblogs, etc.)about the object, accessories for the object, visual enhancements orimprovements to the object, sounds for the object, etc.

Non-limiting examples of the activity applications 214 may include videogames, learning applications, assistive applications, storyboardapplications, collaborative applications, productivity applications,etc. Various non-limiting examples of the virtual environments that canbe rendered by the activity applications 214 are discussed below withreference to at least FIGS. 11A-14.

The camera driver 306 includes software storable in the memory 314 andoperable by the processor 312 to control/operate the camera 110. Forexample, the camera driver 306 is a software driver executable by theprocessor 312 for signaling the camera 110 to capture and provide avideo stream and/or still image, etc. The camera driver 306 is capableof controlling various features of the camera 110 (e.g., flash,aperture, exposure, focal length, etc.). The camera driver 306 may becommunicatively coupled to the camera 110 and the other components ofthe computing device 104 via the bus 308, and these components mayinterface with the camera driver 306 via the bus 308 to capture videoand/or still images using the camera 110.

As discussed elsewhere herein, the camera 110 is a video capture deviceconfigured to capture video of at least the activity surface 102. Thecamera 110 may be coupled to the bus 308 for communication andinteraction with the other components of the computing device 104. Thecamera 110 may include a lens for gathering and focusing light, a photosensor including pixel regions for capturing the focused light and aprocessor for generating image data based on signals provided by thepixel regions. The photo sensor may be any type of photo sensorincluding a charge-coupled device (CCD), a complementarymetal-oxide-semiconductor (CMOS) sensor, a hybrid CCD/CMOS device, etc.The camera 110 may also include any conventional features such as aflash, a zoom lens, etc. The camera 110 may include a microphone (notshown) for capturing sound or may be coupled to a microphone included inanother component of the computing device 104 and/or coupled directly tothe bus 308. In some embodiments, the processor of the camera 110 may becoupled via the bus 308 to store video and/or still image data in thememory 314 and/or provide the video and/or still image data to othercomponents of the computing device 104, such as the detection engine 212and/or activity applications 214.

The storage 310 is an information source for storing and providingaccess to stored data. In some implementations, the storage 310 mayinclude an indexed set of records that correspond to the TI objects thatmay be placed and manipulated by users in the activity scene 116. Insome implementations, records (e.g., image profiles) for the TI objectscan be indexed using unique shapes, moment(s), histogram(s), etc.derived from the TI objects. These indexes may be computed usingoperations that are the same as or substantially similar to thosediscussed below with reference to at least FIGS. 7-8B.

For example, an application developer may create a set of TI objects fora given activity application 214. To enable the detection engine 212 todetect the TI objects, the application developer may create acorresponding set of records for the TI objects for storage in thestorage 310. In other implementations, the storage 310, detector 304,and/or an activity application 214 may include software executable bythe processor 312 to query a server 202 for information that matches apreviously unidentified TI object.

In some implementations, the storage 310 may be included in the memory314 or another storage device coupled to the bus 308. In someimplementations, the storage 310 may be or included in a distributeddata store, such as a cloud-based computing and/or data storage system.In some implementations, the storage 310 may include a databasemanagement system (DBMS). For example, the DBMS could be a structuredquery language (SQL) DBMS. For instance, storage 310 may store data inan object-based data store or multi-dimensional tables comprised of rowsand columns, and may manipulate, i.e., insert, query, update, and/ordelete, data entries stored in the verification data store 106 usingprogrammatic operations (e.g., SQL queries and statements or a similardatabase manipulation library). Additional characteristics, structure,acts, and functionality of the storage 310 is discussed elsewhereherein.

FIG. 4 is a flowchart of an example method 400 for virtualizing tangibleinterface objects. In block 402, the calibrator 302 calibrates thecamera 110. In some implementations, the calibrator 302 performsgeometric and/or image calibration to prepare the camera 110 for TIobject detection and recognition. In block 404, the camera 110 and/orcomputing device 104 are then positioned on or proximate an activitysurface and the video capture device (e.g., the camera 110) captures 406a video stream that includes an activity scene of the activity surfaceand one or more interface objects that are physically intractable withby a user. In some implementations, the detector 304 can signal thecamera 110 to capture the video stream (e.g., via the camera driver 306)and the camera 110 can provide the video stream to the detector 304(e.g., directly, via the memory 314, etc.). As shown in FIGS. 1A-1C, acomputing device 104 that includes the camera 110 may be placed in apreconfigured stand 106 that positions the camera 110 to capture theactivity scene 116 and positions the computing device 104 for viewingand/or interaction with by the user, although numerous furtherconfigurations are possible as described elsewhere herein. In someinstances, the camera 110 may be adapted with the adapter 108 tooptimally adapt the field of view of the camera 110 to capture a regionof the activity surface 102 (e.g., table, wall, etc.) located in frontof the computing device 104.

Next, the detector 304 processes the video stream to detect 408 one ormore TI objects included in the activity scene 116 and identify 410 theone or more TI objects that are detected. FIGS. 5A-9 describe variousexample operations that can be performed by the detector 304 to detectand identify the TI objects, although additional and/or alternativeoperations are also possible and contemplated. The method 400 can thenpresent 412 virtual information on the one or more computing devices 104based on the one or more TI objects that are identified by the detector304. For example, the detector 304 can pass events for the TI objectsdetected and identified by it to one or more activity applications 214for visualization to the user in a virtual scene generated by it basedon the events.

FIGS. 5A and 5B are flowcharts of a further example method 500 forvirtualizing tangible interface objects. In block 502, the calibrator302 may initially perform geometric calibration of the video capturedevice (e.g., camera 110) and then the video capture device may, inblock 504, capture video of one or more scenes. For example, as depictedin FIG. 1C, the camera 110 may capture the activity scene 116 and theuser scene 126. In some instances, the field of view of the camera 110may be split by the adapter 108 into multiple scenes, such as theactivity scene 116 and the user scene 126. For instance, for a frontfacing camera 110, the adapter 108 may leave a portion of the field ofview of the camera 110 unmodified to capture video of the users faceand/or extremities (e.g., hands), and may redirect a portion of thefield of view of the camera 110 downward to capture the activity service102 using a reflective element, such as a mirror, although otherconfigurations are also possible discussed elsewhere herein.

The detector 304 may then determine 506 whether the video received fromthe camera 110 contains a scene including a user (i.e., a user scene),and if so, can process 508 the user scene 126 for user inputs, such asspeech, facial expressions, hand motions, body language, etc. Forexample, the detector 304 may process the facial regions and handregions of a sequence of video images received from the camera 110 todetermine whether the user is gesturing, and if so, may determine whichgestures are being performed and pass those gestures along with any TIobject events that it generates to one or more of the activityapplications 214, as discussed elsewhere herein.

Additionally, the detector 304 may determine 510 whether the videoreceived from the camera 110 contains a scene including the activitysurface 102 (i.e., an activity scene 116), and if so, may proceed todetect 512 one or more TI objects included in the activity scene 116. Ifthe video received from the camera 110 does not include the activityscene 116, the method 400 may return to block 502 to calibrate thecamera 110, proceed to process the user inputs determined in block 508,may return an error prompt to the user indicating there is an issue withthe configuration of the platform, may terminate or wait, etc.

In block 514, the detector 304 may identify the TI object(s) included inthe activity scene 116, determine 516 attributes for those TIobjects(s), and generate 518 corresponding event(s) for the TI object(s)based on their identities and attributes. As described elsewhere herein,attributes that the detector 304 can determine during detection and/oridentification of the TI object(s) may include but are not limited to, aconfidence for the inferred shape of each TI object, whether the objectis obscured and by how much, a confidence for the obscuritydetermination, gestures associated with the TI object(s), etc. One ormore activity applications 214 may receive the object event(s) and/orany user inputs determined by the detector 304, and may execute 520routines in block 420 based thereon. Based on the results produced bythe routines, the one or more activity applications 214 may presentvirtual object-related information in block 522, such as a rich virtualenvironment incorporating digital representations of the TI object(s),to the user(s), as discussed elsewhere herein.

FIGS. 6A and 6B are flowcharts of an example method 600 for tangibleinterface object detection and recognition. In the method 600, thedetector 304 may receive 602 an image of the activity scene 116, process604 the image for the contour(s) of each TI object included in theactivity scene 116, construct 606 an object description for each TIobject based on the contour(s), infer 608 an object shape for each TIobject based on the object description associated with that TI object,and identify 610 generally what each TI object is (e.g., a tile, card,block, game piece, writing utensil, toy, pad of paper, drawing, etc.)based on its inferred shape. FIGS. 5A-9 describes various furtherexample operations that can be performed by the detector 304 to detectthe TI object(s), although additional and/or alternative operations arealso possible and contemplated.

In some implementations, an activity application 214 may specify theshape(s) of the TI object(s) (either directly or in the storage 310)that the detector 304 should look for when performing the objectdetection and identification, and the detector 304 may compare thespecified shape(s) to those it infers from the video data to determinewhat the TI object(s) are. In other implementations, the detector 304may infer the shape(s) of the TI object(s) and query a search engineoperable by the server 202 or another information source (e.g., thestorage 310) to determine what the TI object(s) are.

Next, the detector 304 may determine 612 a confidence in theidentification of the TI object(s) and then determine 616 whether theseconfidence level(s) determined in block 614 meet a predeterminedthreshold. If not, the detector 304 may signal the calibrator 302 tocalibrate 618 the camera 110 to account for the geometry of thevisualization platform. Upon calibrating the camera 110, the method 600may return block 602 and resume from there. If the detector 304determines 616 that the confidence level(s) meet a predeterminedthreshold, the detector 304 processes 620 characteristics of the TIobject(s) to determine the specific identities of the TI object(s).

In some implementations, the TI object(s) include image(s) (e.g.,photos, pictures, graphics, etc., of various items) and the detector 304processes 620 the contour(s) of these image(s), constructs 622description(s) for the image(s) based on the contour(s), and thenidentifies 624 the image(s) based on their description(s). For instance,to identify that a TI object is a card depicting an image of a tree(e.g., see FIGS. 1A-1C), the detector 304 can process the region of theactivity scene image that includes the TI object to construct contoursfor tree, create a description of the tree based on the contours, andquery the storage 310 for a record matching the description.

In some implementations, the TI object detection operations performed inblocks 602-614 may serve to identify the general nature of the TIobject(s), such as what type of objects they are (e.g., round cards,square cards, triangular cards, etc.), and the TI object recognitionoperations performed in blocks 620-624 may serve to determine thespecific identities of the TI object(s) based on unique characteristics(e.g., a unique picture depicted on a visible surface of the TI object)that differentiate the TI object(s) from one another.

Next, the detector 304 proceeds to determine 620 whether it successfullyidentified the characteristic(s) (e.g., image(s)) of the TI object(s).If not, the detector 304 may signal the calibrator 302 to calibrate thecamera for image recognition in block 628, and upon doing so, the method600 may return to block 620 and resume from there. If the detector 304determines 626 that the characteristic(s) (e.g., image(s)) of the TIobject(s) are successfully identified, the detector 304 may determine630 attributes for the images depicted on the TI object(s). One or moreof the activity applications 214 may use the attributes of the TIobject(s) and the images they contain (e.g., based on the eventsreceived from the detector 304) to render 632 an interactive virtualenvironment to the user that incorporates digital representations of theTI object(s), content related to the TI object(s), and/or theenvironmental and/or positional attributes of the TI object(s), asdescribed elsewhere herein.

FIG. 7 is a flowchart of a further example method 700 for TI objectdetection. In block 702, the detector 304 may process the video image ofthe activity scene 116 for contour(s) of each TI object included in theactivity scene 116 and construct 704 a description for each TI object bymapping the contour(s) associated with each of the TI objects using acoordinate system. The detector 304 may then infer 706 the object shapefor each TI object based on the coordinates of the contour(s) associatedwith each TI object, identify 708 the TI object(s) based on the objectshape(s) of the TI object(s), and determine 710 the position and/ororientation of the TI object(s) based on the coordinates of those TIobject(s). For example, the detector 304 may use the coordinates of thecontours of the objects to determine the position and/or orientation ofthe objects. In some cases, the detector 304 may compare the coordinateswith a known point of reference (e.g., the stand 106, positionalinformation associated with the TI objects stored in the storage 310,etc.) to determine the position and/or orientation of the objects.

FIGS. 8A and 8B are flowcharts of a further example method 800 for TIobject recognition. In block 802, the detector 304 may process 802 thevideo image of the activity scene 116 for contour(s) of image(s)contained on the TI object(s) and construct 804 description(s) for theobject image(s) by mapping the contour(s) associated with the image(s)using a coordinate system. The coordinate system may be two or threedimensional in nature and may be configured to reflect the dimensions(scaled or actual) of the activity scene 116, and thus the position ofthe TI object(s) when mapped by the detector 304. Next, the detector 304may calculate 806 moment(s) for the object image(s) based on the mappedcoordinates associated with the image(s). Example moments that can becalculated by the detector 304 may include area moments, perimetermoments, centroid moments, etc. These moments may be calculated based onthe areas, perimeters, etc., of the items depicted by object images ofthe TI object(s). As a further example, the detector 304 may use thecoordinates of the contours for the items it processes from the objectimages to determine perimeters or areas for those items, and may thencompute various moments as unique identifiers for the images using theperimeters or areas. In some instances, the detector 304 may manipulatevarious parameters of the camera to adjust the video images beingcaptured (e.g., contrast, exposure, white balance, levels, etc.) toenhance the contours of the items depicted by the object images.

Alternatively or in addition to block 806, the detector 304 maycalculate 808 color histogram(s) for the object image(s) as uniqueidentifiers for the image(s). The color histogram(s) may be computedbased on the entire image or one or more sections thereof. For instance,the detector 304 may divide the image contained on a given TI objectusing a grid and may compute color histogram(s) for using the image datafrom one or more quadrants of the grid. As a further example, the gridmay be a 4×4 grid that overlays the image containing 16 quadrants andthe detector 304 may compute three color histograms using image datafrom the 1^(st), 5^(th) and 6^(th) quadrants (e.g., counted left toright, top to bottom), respectively. This is advantageous as each imagemay be indexed using different attributes extracted from differentregions of the object image, thus allowing the platform to index morethan one attribute.

The detector 304 may determine 810 positional information for the TIobject(s), such as location and/or orientation of the TI object(s)within the activity scene 116 based on the object and/or imagecoordinates. The detector 304 may also determine 812 whether totransform the moments and/or histograms computed in blocks 606 and/or808 and may then query 814 the a data store, such as storage 310, formatching records (e.g., image profiles) using the moment(s) and/or colorhistogram(s). In some instances, the moments and or histograms may betransformed based on the position of the TI object(s) within theactivity scene 116 (e.g., relative to a point of reference, such as thestand 106).

If matching image profiles are found 816 by querying the data store, thedetector 304 may generate events for the TI object(s) based onattributed information determined by the detector 304 and/or retrievedfrom storage 310, as discussed in further detail elsewhere herein. Ifmatching image profiles are not found in block 816, the detector 304 maysignal the calibrator 302 and/or the user to perform 818 imagecalibration on the camera, and once performed, the method 800 may returnto block 802 and resume processing from there.

In some implementations, to recognize the object images in method 800,the detector 304 may perform the operations of method 830 by sending 832the object image(s), and/or information computed based on the objectimages, such as the moments and/or color histogram, to a server 202coupled to the network 206 for processing and recognition. In response,the detector 304 may receive 834 identification of the image(s) from theserver 202. In some cases, the server 202 may include an image searchengine capable of matching the object image(s), and or informationderived therefrom, to images accessible on the Internet and determinethe identities of the object images based on metadata and/or informationassociated with the Internet images. The search engine may provide thedetector 304 with digital representations of the TI object(s) (and/orinformation supplemental thereto) retrieved from Internet-basedinformation sources (e.g., websites), and the detector 304 may storeand/or provide this information to one or activity applications 214 foruse thereby in generating a virtual environment that incorporates the TIobject(s). In some implementations, one or more of these operations maybe performed by an activity application 214.

FIG. 9 is a flowchart of an example method 900 for detecting changes inthe state of an activity surface.

In block 902, the detector 304 may receive a video image frame of theactivity scene 116, compare 904 the activity scene image to a previouslyreceived image frame of the activity scene 116, determine 906 whether asubstantial difference exists between the image frame of the activityscene 116 and the previously received image frame of the activity scene116, and proceed in block 908 to process the video stream to detect theone or more interface objects included in the activity scene 116 if thesubstantial difference is determined to exist. If in block 906, asubstantial difference is not detected between the current and previousstates of the activity scene 116, the method 900 may wait 910 for thenext image frame and then repeat the operations in at least blocks 902,904, and 906.

By using the method 900, the detection engine 212 may wait for the nextvideo image that actually contains a significant enough change tojustify processing the image for TI object(s). As a further example,during each cycle, the detector 304 may compare a previous andsubsequent video image to determine if there are any significant changesand may refrain from processing the most recent image unless the changessatisfy a predetermined threshold. The method 900 is advantageousbecause it can eliminate unnecessary detection and recognitionprocessing by the platform and thereby avoid bogging down/adverselyaffecting the performance of the computing device 104.

FIG. 10 is a flowchart of an example method 1000 for processing anddisplaying virtual object-related information based on the TI object(s)identified. In block 1002, an activity application 214 may receiveevent(s) for the TI object(s) determined by the detector 304 as presentin the activity scene 116. Based on information included in the one ormore events, the activity application 214 may determine 1004 theidentities of the TI object(s), receive 1006 one or more input(s)associated with the activity scene 116 and/or TI object(s), such asgestures determined from the event(s) provided by the detector 304,gestures derived from information included from event(s) received overtime, user input(s) detected from a user scene 126 by the detector 304,etc., user input(s) received from the user via the input device 318 ofthe computing device 104, etc.

Based on the identities and attributes of the TI object(s), the activityapplication 214 may then execute 1008 one or more routines to generateobject-related information visualizing the one or more interface objectsand may present 1010 the object-related information to the user, asdiscussed elsewhere herein.

It should be understood that the each of the methods 400-1000 are inmany respects compatible with and in some cases expansions one or moreof the other methods, and that further methods based on the combinationof various aspects of these methods are contemplated and within thescope of the present disclosure.

In addition, the methods 400-1000 are advantageous in a number ofrespects including, but not limited to, providing fast and accurate TIobject detection and recognition, providing the user with a real-time,virtualized experience that blends the user's physical interaction withthe TI objects and activity surface 102 and rich, visual andcomputational enhancements that would otherwise be inaccessible to theuser, and adding a meaningful tangible aspect to what can otherwise be atactile-less, largely sterile digital experience.

FIGS. 11A-14 are examples of virtualized scenes on a computing device104 generated based on physical scenes created by users on a physicalactivity surface. In particular, FIGS. 11A-11I depict a series ofincremental changes to a physical activity scene 116 on a physicalactivity surface, which are replicated in a virtual scene 1100 on acomputing device 104. In these figures, each cluster of tiles representsa logical construct that is processed by the activity application 214 torender a unique visual representation of the tiles derived from thecontent, manipulation, and/or relative position of the tiles. Forinstance, in FIG. 11A, a tile bearing an image of the house is placed inthe activity scene 116 and a corresponding virtual scene 1100 thatincludes the house is rendered by activity application 214 forpresentation on the computing device 104 based on the event generatedfor the tile by the detector 304. In subsequent FIGS. 11B-11E,additional tiles bearing different colors and patterns are adjacentlyand abuttingly placed in a cluster in the activity scene 116, and theactivity application 214 analyzes the positions, alignments, and tilecombinations, as determined by the detector 304, to compute the overalleffect of the tile cluster. In this example, the tiles abutted to alower side of the house tile are determined by the activity application214 as having a serialized coloring and patterning affect that compoundsto produce a colorized pattern for the main structure of the house. Incontrast, since the tile including the lined texture is the only tileabutting the house tile on the right, the activity application 214interprets the placement of this tile as an instruction to add thatpattern to the roof of the house as depicted in the virtual scene 1100.

Further, in FIGS. 11F-11I, two more clusters of tiles are placed in theactivity scene 116 (i.e., the sun cluster and the cloud cluster). As aresult, the activity application 214 interprets the arrangement andcontent of each of these clusters to render a sun on the left side ofthe virtual scene 1100 and a summer storm including a dark cloud andrain. In particular, the sun is left unadorned as there are no tilesplaced adjacent to the sun tile in the activity scene 116 and the cloudis colored dark gray and is shown as producing rain based on thearrangement of the tiles in the cloud cluster.

FIGS. 12A-12C depict an example music game. In this game, users canplace tiles depicting different musical instruments in the activityscene 116 and the activity application 214 renders digital audio andvisual representations of the instruments in the virtual scene 1200.Based on the user's interactions with the tiles, the activityapplication 214 can produce different sounds and visual effects for theinstruments that are recognized. For example, in FIG. 12A, a guitar tileis place in the activity scene 116, the detection engine 212 detects theobject as a tile, identifies the images as being a guitar, determinesthe position and orientation of the tile, and creates and provides anevent describing the tile to the activity application 214. The activityapplication extracts the identity of the tile from the event and queriesthe storage 310 for a digital image of the guitar and a music file of aguitar sound, and then reproduces a digital representation of the tilein the virtual scene 1200 in a location that corresponds to the positionof the guitar tile in the activity scene 116 and plays the music file ofthe guitar sound (as indicated by the notes depicted in the virtualscene 1200). Similarly in FIG. 12B, the user places a drum tile in theactivity scene 116 and the activity application 214 renders a drum fordisplay. The activity application 214 can also produce effects based onthe manipulation of the tiles in activity scene 116, as shown in FIG.12C. In this figure, the user waves his/her hand over the guitar tile,and in response, the detection engine 212 detects the obscure gestureassociated with the guitar tile and generates and passes event(s) basedthereon to the activity application 214, which may determine from theevent(s) that the guitar tile has been obscured and render a guitarsound in response (e.g., via a speaker of the computing device 104).

FIGS. 13A-14 depict additional non-limiting variations of virtualizedtangible activities that may be provided to users via the platform. Forinstance, in FIGS. 13A and 13B, a user may draw a landscape including atree and a sun in the activity scene 116 (e.g., on a piece of paper, onwhiteboard or chalkboard, etc.). The activity application 214 may be adrawing application that is configured to interpret what is being drawnand may interact with the detection engine 212 to receive eventsincluding information describing the objects being drawn as well asother items in the activity scene 116 including the writing utensil andthe user's drawing hand. For instance, as with tangible objects, thedetector 304 may determine what is being drawn and communicate thatinformation to the activity application 214. As another example, thedetector 304 may detect and identify the writing utensil and the user'shand to the activity application 214, and the activity application 214may omit those items from display while still reproducing the portion ofthe video images containing the drawing to thereby provide anunobstructed virtual rendering of what is being drawn. In someimplementations, the activity application 214 may use past video framesto reproduce the areas being obscured so the virtual environment mayappear complete even though a portion of the activity scene 116 mayobscured by the user's hand and/or writing utensil. While not depicted,in some implementations, the activity application 214 can enhance theitems being drawn by displaying complementary images (e.g., bushes, apond, animals, etc.) in the virtual scene 1300. These complementaryimages may be retrieved from storage 310 and/or downloaded from thenetwork 206 from another information source.

In FIG. 14, a user may use blocks to portray different real-worldobjects (e.g., a Christmas tree), and the detection engine 212 mayrecognize the objects formed in the physical scene 116 and communicatethat information to the activity application 214, which may then rendera digital representation of the object (e.g., tree) in the virtual scene1400, which may be enhanced by the activity application 214. Forinstance, upon knowing the identity of the object portrayed in theactivity scene 116, the activity application 214 may retrieve acorresponding record from the storage 310 that includes an enhancedvirtual representation of that object and render it for display in thevirtual scene 1400.

It should be understood that the above-described example activities areprovided by way of illustration and not limitation and that numerousadditional use cases are contemplated and encompassed by the presentdisclosure. For instance, white not depicted, by leveraging thedetection engine 212, an activity application 214 may be configured toshare and track the progress of a physical board game between tworemotely located users. Each user may set up the same board game intheir respective activity scenes 116, and the activity application 214on each user's computing device 104 may virtualize the game for displayto the users based on the events received from the detector 304. Forinstance, the activity applications 214 operating on each user'scomputing device 104 may display a synchronized virtual representationof the board game, track and display the movement of the game pieces,compute and display the score, provide tips and or help (e.g., gamerules), etc. The instances of the activity application 214 may staysynchronized by sending one another updates reflecting changes in thestate of the respective activity scenes 116, or by synchronizing via anintermediary (e.g., a server 202). Using this activity application 214,the users can enjoy the tangible gameplay of a board game together whileresiding in disparate geographic locations.

In further non-limiting examples, activity applications 214 could assistvision impaired individuals to learn to read braille using customized TIobjects that include the braille and that are recognizable to thedetection engine 212; re-animate how an image was drawn and share thatre-animation (e.g., in a gif file) via a social network or another imagesharing service with other users; can archive and show the progressionon different objectives a user has been working on, can determinevarious characteristics of different items, such as size, area, etc.,and provide informative supplementation information about such items,etc.

In the above description, for purposes of explanation, numerous specificdetails are set forth in order to provide a thorough understanding ofthe present disclosure. However, it should be understood that thetechnology described herein can be practiced without these specificdetails. Further, various systems, devices, and structures are shown inblock diagram form in order to avoid obscuring the description. Forinstance, various implementations are described as having particularhardware, software, and user interfaces. However, the present disclosureapplies to any type of computing device that can receive data andcommands, and to any peripheral devices providing services.

In some instances, various implementations may be presented herein interms of algorithms and symbolic representations of operations on databits within a computer memory. An algorithm is here, and generally,conceived to be a self-consistent set of operations leading to a desiredresult. The operations are those requiring physical manipulations ofphysical quantities. Usually, though not necessarily, these quantitiestake the form of electrical or magnetic signals capable of being stored,transferred, combined, compared, and otherwise manipulated. It hasproven convenient at times, principally for reasons of common usage, torefer to these signals as bits, values, elements, symbols, characters,terms, numbers, or the like.

It should be borne in mind, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities. Unlessspecifically stated otherwise as apparent from the following discussion,it is appreciated that throughout this disclosure, discussions utilizingterms including “processing,” “computing,” “calculating,” “determining,”“displaying,” or the like, refer to the action and processes of acomputer system, or similar electronic computing device, thatmanipulates and transforms data represented as physical (electronic)quantities within the computer system's registers and memories intoother data similarly represented as physical quantities within thecomputer system memories or registers or other such information storage,transmission or display devices.

Various implementations described herein may relate to an apparatus forperforming the operations herein. This apparatus may be speciallyconstructed for the required purposes, or it may comprise ageneral-purpose computer selectively activated or reconfigured by acomputer program stored in the computer. Such a computer program may bestored in a computer readable storage medium, including, but is notlimited to, any type of disk including floppy disks, optical disks,CD-ROMs, and magnetic disks, read-only memories (ROMs), random accessmemories (RAMs), EPROMs, EEPROMs, magnetic or optical cards, flashmemories including USB keys with non-volatile memory or any type ofmedia suitable for storing electronic instructions, each coupled to acomputer system bus.

The technology described herein can take the form of an entirelyhardware implementation, an entirely software implementation, orimplementations containing both hardware and software elements. Forinstance, the technology may be implemented in software, which includesbut is not limited to firmware, resident software, microcode, etc.Furthermore, the technology can take the form of a computer programproduct accessible from a computer-usable or computer-readable mediumproviding program code for use by or in connection with a computer orany instruction execution system. For the purposes of this description,a computer-usable or computer readable medium can be any non-transitorystorage apparatus that can contain, store, communicate, propagate, ortransport the program for use by or in connection with the instructionexecution system, apparatus, or device.

A data processing system suitable for storing and/or executing programcode may include at least one processor coupled directly or indirectlyto memory elements through a system bus. The memory elements can includelocal memory employed during actual execution of the program code, bulkstorage, and cache memories that provide temporary storage of at leastsome program code in order to reduce the number of times code must beretrieved from bulk storage during execution. Input/output or I/Odevices (including but not limited to keyboards, displays, pointingdevices, etc.) can be coupled to the system either directly or throughintervening I/O controllers.

Network adapters may also be coupled to the system to enable the dataprocessing system to become coupled to other data processing systems,storage devices, remote printers, etc., through intervening privateand/or public networks. Wireless (e.g., Wi-Fi™) transceivers, Ethernetadapters, and modems, are just a few examples of network adapters. Theprivate and public networks may have any number of configurations and/ortopologies. Data may be transmitted between these devices via thenetworks using a variety of different communication protocols including,for example, various Internet layer, transport layer, or applicationlayer protocols. For example, data may be transmitted via the networksusing transmission control protocol/Internet protocol (TCP/IP), userdatagram protocol (UDP), transmission control protocol (TCP), hypertexttransfer protocol (HTTP), secure hypertext transfer protocol (HTTPS),dynamic adaptive streaming over HTTP (DASH), real-time streamingprotocol (RTSP), real-time transport protocol (RTP) and the real-timetransport control protocol (RTCP), voice over Internet protocol (VOIP),file transfer protocol (FTP), WebSocket (WS), wireless access protocol(WAP), various messaging protocols (SMS, MMS, XMS, IMAP, SMTP, POP,WebDAV, etc.), or other known protocols.

Finally, the structure, algorithms, and/or interfaces presented hereinare not inherently related to any particular computer or otherapparatus. Various general-purpose systems may be used with programs inaccordance with the teachings herein, or it may prove convenient toconstruct more specialized apparatus to perform the required methodblocks. The required structure for a variety of these systems willappear from the description above. In addition, the specification is notdescribed with reference to any particular programming language. It willbe appreciated that a variety of programming languages may be used toimplement the teachings of the specification as described herein.

The foregoing description has been presented for the purposes ofillustration and description. It is not intended to be exhaustive or tolimit the specification to the precise form disclosed. Manymodifications and variations are possible in light of the aboveteaching. It is intended that the scope of the disclosure be limited notby this detailed description, but rather by the claims of thisapplication. As will be understood by those familiar with the art, thespecification may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. Likewise, theparticular naming and division of the modules, routines, features,attributes, methodologies and other aspects are not mandatory orsignificant, and the mechanisms that implement the specification or itsfeatures may have different names, divisions and/or formats.

Furthermore, the modules, routines, features, attributes, methodologiesand other aspects of the disclosure can be implemented as software,hardware, firmware, or any combination of the foregoing. Also, wherevera component, an example of which is a module, of the specification isimplemented as software, the component can be implemented as astandalone program, as part of a larger program, as a plurality ofseparate programs, as a statically or dynamically linked library, as akernel loadable module, as a device driver, and/or in every and anyother way known now or in the future. Additionally, the disclosure is inno way limited to implementation in any specific programming language,or for any specific operating system or environment. Accordingly, thedisclosure is intended to be illustrative, but not limiting, of thescope of the subject matter set forth in the following claims.

What is claimed is:
 1. A camera adapter comprising: a housing configuredto retain and position an optical element; and a connector configured todetachably connect the housing to a computing device situated on anactivity surface such that the housing covers at least a portion of afield of view of a video capture device of the computing device that isfacing forward and the optical element adapts at least a portion of thefield of view of the video capture device to face downward toward theactivity surface.
 2. The camera adapter of claim 1, wherein the opticalelement is positioned at an angle within the housing to redirect thefield of view of the video capture device toward the activity surfaceand the activity surface is located proximate to the computing device.3. The camera adapter of claim 1, wherein the optical element redirectslight reflected from the activity surface into the video capture deviceto capture at least a portion of the activity surface by the videocapture device, the optical element having an optical effect thatmodifies the portion of the activity surface being captured by the videocapture device.
 4. The camera adapter of claim 3, wherein: the opticalelement is a convex mirror having a fisheye effect that enlarges theportion of the activity surface being captured by the video capturedevice.
 5. The camera adapter of claim 1, wherein the optical elementincludes one or more optical components that adapt a first portion ofthe field of view of the video capture device and leave a second portionof the field of view of the video capture device unaltered.
 6. Thecamera adapter of claim 5, wherein: the optical element redirects thefirst portion of the field of view of the video capture device towardthe activity surface to capture an activity scene of the activitysurface; and the optical element leaves the second portion of the fieldof view of the video capture device unaltered to capture a user scene ofa user facing the computing device.
 7. The camera adapter of claim 1,wherein: the optical element includes a mirror, the mirror including areflective layer positioned on a front side of a base surface, thereflective layer substantially reflecting light off the reflective layerwithout passing the light through the base surface.
 8. The cameraadapter of claim 7, wherein: the mirror includes a coating layerpositioned on a front side of the reflective layer, the coating layerhaving a thickness satisfying a thickness threshold.
 9. The cameraadapter of claim 1, wherein: the camera adapter is compatibly placeablein a channel that is formed in a stand configured to receive and retainthe computing device.
 10. The camera adapter of claim 9, wherein: thecamera adapter and the stand include compatible magnets to magneticallysecure the camera adapter in the channel of the stand when the cameraadapter is placed in the channel.
 11. The camera adapter of claim 1,wherein: the video capture device is located on a rear surface of thecomputing device; and the optical element is positioned at an anglewithin the housing to redirect light reflected from the activity surfacelocated in front of the computing device into the video capture device.12. A camera adapter comprising: a housing configured to retain andposition an optical element; and a slot in a bottom side of the housing,the slot being configured to detachably connect to an edge of acomputing device such that the housing covers at least a portion of avideo capture device of the computing device and the optical elementsplits a field of view of the video capture device into a first portionof the field of view and a second portion of the field of view andredirects the first portion of the field of view toward an activitysurface.
 13. The camera adapter of claim 12, wherein the optical elementredirects the first portion of the field of view of the video capturedevice downward to capture an activity scene of the activity surfacelocated proximate to the computing device; and the optical elementleaves the second portion of the field of view of the video capturedevice unaltered to capture a user scene of a user facing the computingdevice.
 14. The camera adapter of claim 12, wherein the optical elementhas an optical effect that modifies a portion of the activity surfacebeing captured by the video capture device.
 15. The camera adapter ofclaim 12, wherein the optical element redirects the first portion of thefield of view of the video capture device to a first portion of theactivity surface to capture a first activity scene of the activitysurface; and the optical element redirects the second portion of thefield of view of the video capture device to a second portion of theactivity surface to capture a second activity scene of the activitysurface.
 16. A camera adapter comprising: an optical element housingincluding a front portion connected to a first side portion and a secondside portion to form a recession space in the optical element housing;and a slot formed on the first side portion and the second side portionof the optical element housing to receive an edge of a computing devicesuch that a video capture device of the computing device faces therecession space and the video capture device is covered by the opticalelement housing; and an optical element positioned at an angle in therecession space of the optical element housing to adapt a field of viewof the video capture device.
 17. The camera adapter of claim 16,wherein: the optical element redirects at least a portion of the fieldof view of the video capture device toward an activity surface locatedproximate to the computing device.
 18. The camera adapter of claim 16,wherein: the slot includes a first edge resting on a front surface ofthe computing device and a second edge resting on a back surface of thecomputing device when the optical element housing is situated on theedge of the computing device.
 19. The camera adapter of claim 18,wherein: the first edge of the slot is flat; the back surface of thecomputing device is curved; and the second edge of the slot is curved tobe compatible with the curved back surface of the computing device. 20.The camera adapter of claim 18, wherein: the second edge of the slotincludes a retaining element to securely retain the optical elementhousing against the back surface of the computing device when theoptical element housing is situated on the edge of the computing device.